[2] He became a regular reader of 2000 AD at the age of ten[3] and started reading American comics after picking up an issue of Swamp Thing written by Alan Moore.

[6] Staying with the magazine for two years, Diggle has been credited (most frequently by David Bishop, who originally hired him for Judge Dredd Megazine) for spearheading a return to the "old school" values of 2000 AD.

That same year, Diggle and Jock both signed an exclusive 2-year contract with DC[12] and launched the Eagle Award-winning and Eisner Award-nominated series The Losers that was later adapted into a feature film of the same name.

[26][27] Diggle's storyline, which began in the Dark Reign: The List—Daredevil one-shot and continued with issue #501 of Daredevil,[28][29] was initially planned to be told in the ongoing series, but Marvel offered to expand it into a small-scale crossover event for the company's "street-level" characters.

[30][31] The crossover event, titled "Shadowland",[32] ran for three months, with Diggle writing the core 5-issue mini-series and co-writing the tie-in storyline in Daredevil with Antony Johnston.

[35][37] In 2012, Diggle returned to British comics with the first fully creator-owned collaboration between himself and Jock, Snapshot,[38] originally serialized in Judge Dredd Megazine and subsequently reprinted for the American market,[39] and a new installment of Lenny Zero, illustrated by Ben Willsher.

[45][46] Diggle announced his exit from the title shortly thereafter, one month before the release of his first issue, citing "professional reasons", with Tony Daniel taking over the writing duties.